No abstract

A novel galactose-specific lectin, AJLec (18.5 kDa), was isolated from the sea anemone, Anthopleura japonica. AJLec was characterized using the hemagglutination assay, isothermal titration calorimetry (ITC), and glycoconjugate microarray analysis and we found that AJLec has a specificity for galactose monomers and β-linked terminal galactose residues in complex carbohydrates, but not for N-acetylgalactosamine (GalNAc), which is commonly recognized by galactose-binding lectins. The primary structure of AJLec did not show homology with known lectins, and a crystal structural analysis also revealed a unique homodimeric structure. The crystal structure of AJLec complexed with lactose was solved by measuring the sulfur single-wavelength anomalous diffraction (S-SAD) phasing with an in-house Cu Kα source method. This analysis revealed that the galactose residue in lactose was recognized via its O2, O3, and O4 hydroxyl groups and ring oxygen by calcium coordination and two hydrogen bonds with residues in the carbohydrate-binding site, which demonstrated strict specificity for the β-linked terminal galactose in this lectin.

A new flavonoid, quercetin 3- O-α-L-rhamnopyranosyl-(1→6)-(2- E- p-coumaroyl)-β-D-glucopyranoside-4′- O-α-L-rhamnopyranoside, was isolated from the fermented tea of Camellia sinensis L. (Pu-erh tea) from China. The chemical structure was elucidated based on analyses of the spectroscopic data.

By incorporating the environmental problems caused by consumption into a theoretical model of rural-urban migration, this study analyzes the effect of a reduction in pollution generation rate and factor accumulation. The environment of each rural and urban area is assumed to deteriorate due to pollution from consumption of the respective inhabitants. For institutional reasons, the urban wage rate is fixed at a higher level than the rural wage rate, and unemployment exists in the urban area. Rural-urban migration occurs because of differences in utility, which is affected by both the environment and expected earning in each area. This study shows that, although reduction in the pollution generation rate improves the environment in both areas, whether it mitigates urban unemployment depends on certain conditions. Regarding the effect of factor accumulation, this study shows that an increase in capital endowment decreases the level of unemployment if and only if the environmental effect outweighs the Rybczynski effect.

By incorporating the environment into the Harris-Todaro model, this paper examines how